Research

Dr. Liu's research interests include the development of miniaturized analysis system for biological and environmental applications. This type of analyzer can integrate sample collection, injection, separation, and detection on a single microfluidic device. Current undergoing projects include:

Separations on microfluidic device.
Different separation methods (CE and CEC) will be adapted from conventional analysis system to the microfluidic device format. Surface chemistry of polymer-based device is being studied to facilitate more efficient separations. Currently, the surfactant and polyelectrolytes are under investigation.

Portable analyzer for real-time monitoring of aerosolThe amount of components in air-borne particles is directly related to the anthropological activities. Air sample will be collected and deposited directly onto the microfluidic device, followed by the CE separation and detections. The species we are interested in include sulfate, nitrate, ammonium, and some organic acids.

Caffeine in energy drinks
Energy drinks contain high levels of caffeine and other stimulants. High-dose consumption of energy drinks could potentially lead to the death of human beings. We are developing a new analyzer for fast determination in energy drinks and/or body fluid.

Electrochemical properties of grapheneGraphene, a two-dimensional crystal consisting of a monolayer of carbon atoms arranged in a honeycomb lattice, exhibits unique electrical properties. We are characterizing the surface and electrical properties of nitrogen-doped graphene via electrochemical and spectroscopic methods.